knotting

[hammer n nails]

Brought some stuff called knotting (think thats what its called) The guy in the shop said its good to stop sap coming out of the wood now do i coat the whole of the wood or just cover the knots, after this has been applyed can you use danish oil over it or just varnish sorry to ask but i am a novice at woodworking thanks guys

 

[Chems]

Just cover the knots, I think its designed for when your painting wood not oiling it but not sure on that.

 

[hammer n nails]

anyone else got any ideas, thank you for your reply

 

[Rob Platt]

As chems said its to seal the knot and to stop it bleeding through the paintwork just do the knot if you feel a need to. never bothered myself if i wasn`t painting but it may be different depending on what you`re doing. all the best
rob

 

[Eric The Viking]

Knotting is very useful for painted pine (a.k.a. softwood or deal). You'll otherwise find that modern oil-based paint finishes (white particularly) stain yellow, around the area of the knot, if it isn't sealed.

Aluminium primer also stops this happening, and it also stops/delays the onset of rot outdoors, but it's hugely expensive in comparison.

 

[bosshogg]

Knotting was always applied to knots of resin's woods in particular, as eric the viking has said, but I'm talking prior to french polishing rather than painting. Once applied and set it should be cabinet scraped back, so that none is left on the surface, this way you achieve the finish you want and no problems with blemishing around the knots.
Also with modern stain applications it's always advisable to use it...I remember Scandinavian softwood windows that were fitted to a housing development, all stained white, that the knots started to become visible within months of completion, turned out this was due to the manufacturers missing out the knotting before applying the stain...very expensive mistake, for them. I had them stripping all the windows too about forty houses, applying the knotting and re staining them on site (houses were occupied) took weeks...bosshogg :|

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